<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    *{
        margin: 0;
        padding: 0;
       
    }
    .box{
        width: 220px;
        height: 280px;
        background-color: red;
        margin: 100px auto;
      
    }
    .a{
        display: flex;
    }
    .aa{
        width: 150px;
        height: 160px;
    }
    .d{
        margin-left: 5px;
    }
    .b{
        margin-top: 5px;
    }

</style>
<body>
    <div class="box">
           <div class="a">  
             <div class="c"><img src="./img/small_1.jpg" alt="" class="aa"></div>
            <div class="d"> 
             <img class="e" src="./img/small_1.jpg" alt="">
             <img class="e" src="./img/small_2.jpg" alt="">
             <img  class="e" src="./img/small_3.jpg" alt=""></div>
           </div>

           <div class="b">
             
             <img class="e" src="./img/small_4.jpg" alt="">
             <img class="e" src="./img/small_5.jpg" alt="">
             <img class="e" src="./img/small_6.jpg" alt="">
             <img class="e" src="./img/small_7.jpg" alt="">
             <img class="e" src="./img/small_8.jpg" alt="">
             <img class="e" src="./img/small_9.jpg" alt="">
             <img class="e" src="./img/small_10.jpg" alt="">
             <img class="e" src="./img/small_11.jpg" alt="">
           </div >
    </div>
</body>
<script>
    var aa=document.querySelector('.aa')
    var ee=document.querySelectorAll('.e')
    for(var i=0;i<ee.length;i++){
        ee[i].index=(i+1)
        ee[i].onmousemove=function(){
            aa.src="./img/small_"+this.index+'.jpg'
        }
    }
</script>
</html>